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Amp Wiring Kit and subwoofer recommendation!

Just got my tower speakers, amp, and subwoofer to beef up the audio system in my 2008 Outback V (see below for details). I'm hoping to get some help figuring out if there are any good off-the-shelf wiring kits available that I can pick up for a reasonable $ value.
As always, the fantastic advice from everybody on the forum would be GREAT! Thanks in advance!

Head Unit: Stock
Amplifier: WetSounds HT-6 bridged to 300Wx3 channels (4 ohms)
Tower Speakers: Wetsounds Pro-80's
Subwoofer: Kicker Solo-Baric 12L72
- This is actually a 2 ohm subwoofer where as the amp is meant to deliver 4ohm load. I am planning on getting a new subwoofer if there is no way I can accommodate this. Any recommendations?
- Any 12"woofers that can handle the 300W RMS load with similar sealed volume requirements?
- If at all possible I'd like to keep it cheaper than the JL 12W6v2-D4...but if you gotta you gotta right?

Amp Wiring Kit: Any recommendations? Good place to buy?
- Based on the amplifier draw I was planning on using a 4awg kit from automotive application.

The Kicker 12L72 is a dual 2 ohm voice coil sub, so wired in series, it will be a 4 ohm load on the amp. Did you just buy all this gear? If so, I would exchange the L7 for the L3 as it will be a much better match for the HT-6's available 300W rms. Or, exchange the Ht-6 for an HT-4 and HT-1. This option would be the same power to your Pro-80. Although I would like to see 750 to 1000 watts rms to an L7 12", 600W is far better then 300.

You can scratch off the 12w6 from your list. They come in 4 ohm dvc only. You would have to wire it in series in order to bridge it on the HT-6 and it would only receive 220W. That sub deserves 500W or more.

4ga cabling would be the correct size for the HT-6, but the issue with an automotive amp install kit is the 2ft of ground cable they provide. This wont cut it in a boat because both the POS and GND need to terminate at the battery/switch. In a car, the whole chassis is a ground plane, hence the short ground cable. You are better off buying the cable in bulk. Also, buy the RCA cable based on the length needed.

I was thinking the sub would be a good choice in the case I wanted to move the 6 channel to the in boat speaker next year, and replace the amps for the sub and towers.
Is there really any danger for using the sub under powered? Will it sound terrible?

I was thinking the sub would be a good choice in the case I wanted to move the 6 channel to the in boat speaker next year, and replace the amps for the sub and towers.
Is there really any danger for using the sub under powered? Will it sound terrible?

Only too much power and too much abuse hurts speakers. While you could possibly do damage to a tweeter or fullrange speaker by over-driving an under-sized amplifier into more of a compressed/continuous mode, it is very unlikely that you would hurt a subwoofer with that voice coil capacity by under-powering it to that degree. The sub simply will not come close to its potential and a smaller amplifier can reach its limit earlier when driving a woofer like the L7 which is pretty darn demanding.

Distortion is what hurts speakers. And this can happen regardless of what amplifier you have on the sub. Keep your system cleanly powered at whatever level you choose and your gains setup appropriately for your amplifier and you'll be just fine.

It depends on how you define distortion.
A woofer cannot recognize high levels of various types of distortion and distortion does not necessarily create more heat. Over-driving a guitar tube amplifier input for example is a common technique to create a specific effect. The woofer may not recognize this as distortion although we can clearly hear the signal distortion.
Hard compression and clipping directly translate to more continuous power and that is precisely what creates the heat that damages speakers. Power KILLS woofers. Period. If you drive a smaller amplifier into hard clipping you have created more continuous power and the result is more heat.

It depends on how you define distortion.
A woofer cannot recognize high levels of various types of distortion and distortion does not necessarily create more heat. Over-driving a guitar tube amplifier input for example is a common technique to create a specific effect. The woofer may not recognize this as distortion although we can clearly hear the signal distortion.
Hard compression and clipping directly translate to more continuous power and that is precisely what creates the heat that damages speakers. Power KILLS woofers. Period. If you drive a smaller amplifier into hard clipping you have created more continuous power and the result is more heat.

David

I guess we have to agree to disagree here. I personally have yet to ever see a single user apply harmonic distortion as an effect in the marine environment. I think your kinda arguing semantics. Thats totally different than the distortion I'm speaking about. In the every day world about 80% of the woofer failures we warranty a given year as a speaker manufacturer are from sustained heat build up in the gap (the area where the voice coil resides). Approximately 20% of the claims are due to mechanical (torn spiders or rubber surrounds or glue delimitation). This is fairly typical in my experience within the industry.

I think the take away here is that good clean power is what I recommend. Clipping from the head unit or the amplifier will lead to ugliness. I could get super technical and explain how that all happens but it really doesn't matter. The result is the same - sustained heat build up and warped coils.

Back to the OP: under powering a woofer can create heat build up and result in failure IF your operating the amplifier beyond its limits. You cant just keep turning up up up and away the music. At some point your woofer will get into trouble and Poof. Lets keep it that simple.

Yes. It's crazy simple.
Power + Resistance = Heat. You can't make it any more simple than that.
The manifestation of driving an amplifier into clipping is a ratio of more continuous power versus dynamic power. And ultimately it is the sustained power and nothing else that creates the heat.

Brian, you are failing to use the words AMPLIFIER CLIPPING when describing distortion... It is this omission that I find fault with in your description. Distortion does NOT kill speakers, CLIPPING does. Let me explain.

You say you have yet to see a single user apply harmonic distortion, yet every dude who over-drives the AUX input from the headphone output of his MP3 player is applying harmonic distortion. Similarly, someone who has his gains turned way too far down, (like that ever happens ) will introduce harmonic distortion when he cranks his head unit way up past its sinusoidal output limit. Same thing for the guy who turns the bass and treble way up with the LOUDNESS control on, (again, with gains too low).

In every one of these situations the sound will be pretty much awful, as there can and will be some very gross distortion going on. Feed that harmonic distortion to the amp and it will send it to the speakers, but as long as the amp is working within its non-clipped output capabilites the bad sound is not going to tear up the speakers. In this instance the amp is sending a heavily distorted signal to the speaker, yet it is not a CLIPPED signal; any speaker can play it faithfully without fear of damage. That it sounds bad is not the reason it blows. Think of white noise, that is the ultimate distortion, yet it never takes out speakers. These very real world scenarios are just like the over-driven preamplifer section on a guitar amp. It is only the preamplifer that is clipping, and the power amplifier section of the amp is driving the speaker within normal output levels, so it is not clipping. Heavy distortion, yet no blown speaker.

In any audio signal chain before the amplifer, regardless how badly you clip, distort, abuse, re-eq, compress, or otherwise torture the original signal, you are really only adding "effects" to the original signal. Feed this distortion-affected signal to any amp operating within its limts and it will work just fine.

The only time you go start tearing up speakers is when you try to run the final power amplification stage at such a high level that the signal doesn't "fit" between the + and - supply rails of the poweroutputs on the amplifer. CLIPPING DISTORTION is the audible artifact, that you can see on an oscilloscope, showing up as flat spots at the tops and bottoms of the waveform, where the amplifier is no longer operating sinusoidally. David and I argue semantically about how to describe this phenomenon that burns voice coils, but the net effect is the same: burned voice coils.

Bottom line, CLIPPING distortion eats up speakers. All other distortion is simply noise/sound/signal for the amp to recreate. If the amp is operating within its normal range, the speakers will play whatever is fed into the amp just fine.